Why does extracting a metal by electrolysis use large amounts of energy?
The electricity is needed only to melt the ionic compound
The heating is needed only to make the ions move faster
The electricity is cheap because the current used is small
Energy is needed to melt the compound and to make the current
76 exam-style questions on AQA GCSE Chemistry 4.3 Electrolysis, covering 4.3.1a The process of electrolysis, 4.3.1b Half equations in electrolysis, 4.3.2 Electrolysis of molten ionic compounds, 4.3.3 Using electrolysis to extract metals, 4.3.4 Electrolysis of aqueous solutions, and 4.3.5 Representation of reactions at electrodes as half equations. Each one has a worked solution and a mark scheme showing where the marks go.